2003/08/01 by Kun Hu, Plamen Ch. Ivanov, Zhi Chen +3 · 167 citations
Biochemistry, Genetics and Molecular Biology · Computer Science · Economics, Econometrics and Finance · Environmental Science · Mathematics · Physics and Astronomy · Psychology · #Anatomy #Biological system #Biology #Complex Systems and Time Series Analysis #Computer science #Dynamics (music) #Ecosystem dynamics and resilience #Forearm #Fractal #Mathematical analysis #Mathematics #Nonlinear system #Physics #Psychology #Scale (ratio) #Statistical physics #Time Series Analysis and Forecasting #physics.bio-ph #physics.data-an #q-bio.QM
paper · pdf · doi:10.1016/j.physa.2004.01.042
published in Physica A Statistical Mechanics and its Applications 337(1-2), 307-318 (Elsevier BV) · 4 pages, three figures
arxiv created 2003/08/01 · openalex publication_date 2004/03/06 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate if known extrinsic and intrinsic factors fully account for the complex features observed in recordings of human activity as measured from forearm motion in subjects undergoing their regular daily routine. We demonstrate that the apparently random forearm motion possesses previously unrecognized dynamic patterns characterized by fractal and nonlinear dynamics. These patterns are unaffected by changes in the average activity level, and persist when the same subjects undergo time-isolation laboratory experiments designed to account for the circadian phase and to control the known extrinsic factors. We attribute these patterns to a novel intrinsic multi-scale dynamic regulation of human activity.